Method for controlling nematodes



llnited, States Patent 2,895,869 METHOD FOR coNrRoLLmG NEMATODES NoDrawing. Application October 6, 1954 Serial No. 460,755

6 Claims. (Cl. 167-22) This invention relates to improvements in thecontrol of soil-infesting organisms, and more particularly relates 'tonew and improved toxic substances for the control of nematodes and otherparasitical organisms, as well-as methods for their use.

The expression soil-infesting organism, as used in the specification andclaims, is intended to include various organisms, such as wire worms,grubs, maggots, and nematodes, or eel worms. Such organisms have beenamong the most diflicult crop pests to control because of theirresistance to prior soil fumi-gants and other treating substances, andbecause of their ability to survive in the soil for extended periods oftime, even in the absence of host .plants.. Although specific referenceis made here- '1" inafter to the control of nematodes, it will beunderstood, I of course, that the present invention contemplates thecon- 2 trol of various soil-infesting organisms and parasitical wormsand is not limited to the control of nematodes. Plants attacked bynematodes are damaged primarily due to the feeding of the nematodes onplant tissues. Such attacks may destroy plant cells or simply interferewith their normal function. The most common type of ..nematode damage ismanifested as a destruction of the attacked parts and adjacenttissue,.or the growth of galls, root-knobs or other abnormalities. Oneof the most easily recognized diseases is that of so-called root-knotdisease. Such root-knots, or galls, contain nematodes, nematode eggmasses and/ or larvae. Such gall formation in the root system of a plantnot only reduces the size and effectiveness of the root system byrotting or otherwise destroying the roots, but also seriously affectsother plant tissues, with the result that unless treated, the plantdies. Even in those instances where plants attacked by nematodes are notcompletely destroyed, the plants generally are weakened, even thoughthere may be no visible injury to any part of the plant above theground. Although in the past various nematocidal agents have beensuggested and used, the problem of nematode soil infestation remains aserious one.

One of the most effective prior methods for destroying suchsoil-infesting organisms involves the treatment of the soil with steam.In many instances, such a procedure is highly advantageous, because notonly are the nematodes and other organisms destroyed, but also the soilis substantially sterilized. However, it will be understood, of course,that such a treatment is highly impracticable in applications other thangreenhouse frames or similar relatively small installations.

Another prior control method involves the use of chloropicrin 'as a soilfumigant. While chloropicrin is an effective nematocide, in manyinstances it is quite toxic to growing plants and its use requires thatcertain precautions be observed to avoid plant damage. Moreover, in somecases, difficulties are involved in obtaining an optimum nematocidaleifect since some type of liquid seal over the treated soil frequentlyis necessary to retain the vapors in the soil for a sufiicient period oftime.

Another substance which has been proposed and used Patented July 21,1959

, 2 in the control of nematodes is the so-called DD mixture(dichloropropane-dichloropropene). While this substance avoids certainof the difiiculties encountered in other nematocides, it also has failedto provide a complete solution to the problem of nematode control.

It is therefore a principal object of this invention to provide new andimproved toxic substances which are useful in control of nematodes andother soil-infesting organisms.

A further object of the invention is the provision of improved methodsfor controlling nematodes and other soil-infesting organisms.

A still further object of the invention is to provide novel compositionsof matter particularly useful in the control of nematodes and othersoilinfestating organisms.

These and other objects and advantages will appear more fully in thefollowing description of the invention.

The present invention contemplates the use, in the .control of soil-infesting organisms, of compounds having the following formula:

wherein n is a number from 0 to 3,inclusive, X is a halogen, and R isselected from the group consisting of hydrogen, lower alkyl, phenyl,naphthyl, tolyl, xylyl, benzyl and phenethyl radicals.

Typical compounds of 'the above type are dihalogenated andtrihalogenated compounds, which have the following general formulas:

wherein X, and R are as defined before. I V

Illustrative of specific compounds of the foregoing types are3,3,3-trichloro-1-nitropropene, 1,1,1-trichloro-3 -nitr02-butene,

1,1, l-trichloro-3 -m'tro-2-p entene, 3,3-dichloro-l-nitropropene,3,3-dichloro-l-nitro-l-phenylpropene,3,3,3-trichloro-l-nitro-l-phenylpropene,3,3-dichloro-l-nitro-l-phenethylpropene,3,3,3-trichloro-1-nitro-l-phenethylpropene, and.3,3,3-trichloro-1-benzyl-l-nitropropene.

Compoundsof this invention may be employed in a variety of compositionsfor use in nematocides. The nature of these compositions will depend, toa large degree, upon the particular application contemplated. Hence,they may be utilized in any conventional manner, as in soil applicationby spraying, drenching, or dusting. In addition, in many instances it isadvantageous to introduce composition of the invention'directly into thesoil by hand or mechanical sub-soil injectors. Generally, superiorresults are obtained in sub-soil applications when the novelcompositions of this invention are introduced into the soil to a depthof 6" or less. The term, soil, as used herein, is intended to includeany substance or medium capable of supporting the growth of plants. Itis therefore intended to include, in addition to soil, humus, manure,compost, sand, and artificially-created plant growth media, includingsolutions andlor other hydroponic media.

Compositions of this invention may also be embodied in dusting compoundscontaining carriers or fillers, such as talc, sand, dry soil, celite,kaolin, fullers earth, kieselguhr, diatomaceous earthfchalk, gypsum,pyrophyllite, or other inorganic or organic materials, includingactiveingredients, such as fertilizers,;insecticides, fungicides, and/orherbicides. Similarly, if a liquid drench or spray I material isdesired, a composition of the invention may I i be formulated as aliquid using as a :carrier material I I various; solvents, 'diluents, iextenders, and thedike, such 'as'water, aromatic and'aliphatie organicliquids, such as acetone, benzene, and/or'various alcohols,ethers,ketoncs,

and the like, as well as various petroleum fractions.

' I 7 Liquid compositions may alsocontainminor quantities of one ormoreWetting agents, such as iIgepalCO -SSO 7 (alkylphenoxypolyoxyethyleneiethanol), Arquad 2C aternary' ammonium compoundof the formula y ethylated'fatt'y' alcohol), Tween 80 (.polyoxyethylenesor bitan. monooleate), Triton 'X-155 -(alkyl aryl polyether I 5alcohol), Tremy615 (polyhydric alcohol ester), Tween [85(polyoxyethylenesorbitan trioleate) Nonie 218 (polyethylene glycoltertdodec'yl 'thioether), Santomer'seD (decylbenzene; sodium sulfonate),Pluronic F -6 8 (coni densate of. ethylene oxide with an hydrophobic;base 1 formed by condensing propylene oxide with propylene glycol),Antarox'A400 (alkyl phenoxypolyoxyethylene ethanol), Triton 'X-120(alkyl 'aryl polyether alcohol),

NacconoI NRSF (alkyl 'aryl su'lfonate), Aresol OS (iso- I propylna'phthylene sodiumsulfonate), Span 40 (sorbitan ,monopalmitate), TritonB-1956, '(modifiedphthalic glyc- I I i erol alkyd resin)',"and Antaro'x13 -290 (polyoxyethyl'ated;

vegetableoilLI j I I I '0', w Compounds of the "present inventionpreferably are I t I f prepared by'r'eaction of a halogenated aldehyde;orketone and. a substituted 'or'uns'ubstituted nitro compound in a iweakly: alkalinemedium with subsequent dehydration of the halogenatednitroalcohol. For example, 3,3,3-tri- I 1 chloro-I-nitropropene can .beprepared by reactingchloral and nitromethane with subsequent dehydrationof the I r I 1,1,1+trichloro3-nitro+2'p1 opanol; Illustrative ofsuitableI dehydrating agents are aceticanhydride and phosphorus:

' pentoxide.= -While. dehydration of ahalo'gena'ted nitro i alcoholatrpresent is a preferred method of preparing compounds embodying .the.invention, it will be under stood, on course, that such compounds may'beprepared by other methods.

Nematocidal activity of compositions embodying the invention may bedetermined in the following manner: one-half gallon glazed crooks havingan opening in the bottom are filled with screened, composted soil. Thissoil is then inoculated with root nematode galls obtained from tomatoplants infested with the so-called Tomato Root Nematode (Meloidogyneincognita). Such galls vary in size from about /s" to A" in diameter. 5gms. of tomato roots, cut into pieces about /2" long, are mixed with thethus treated soil in each one-half gallon crock.

The crooks are then Watered lightly and allowed to stand over night.Soil additives of this invention, if in liquid form and volatile, areinjected in the center of the crock to a depth of about 3" at varyingdosages in difierent tests. If in solid or powder form, the additivesare mixed thoroughly with the soil in similar dosages. After the soil isthus treated, the crooks are watered frequently to maintain desiredmoisture content and are allowed to stand for days, at which time anumber of test seeds, e.g., typically squash seeds, are planted in eachcrock. Two control crocks are similarly prepared. Results are taken inabout days after the seeds are planted. The infestation, i.e., thenumber of galls, is determined either by placing the roots in water in alarge Petri dish, or when the roots are heavily infested the degree ofinfestation is estimated by comparison with the control plants, to whichno soil additives have been introduced.

In order that those skilled in the art may more completely understandthis invention and the method by which the same may be carried intoeliect, the following specific examples are offered:

EXAMPLE, I. I I

I Preparation of 1,1,1-trirhloro-3-rritro+2 butene.+lntoI I ,5. a 500ml,3-neck,.round bottom flask equipped with a t thermometer, droppingfunnel, 'andstirrerare introduced i 445' gms.of1,1,l-trichlorO-S-nitrbbutanol-Z and 45 ml. of 95% acetic anhydrideand a drop of concentrated sulfuric acid. 20 gms. of sodium acetate isthen added and I I 10' the resultant mixture: refluxedj for lhour. Thismixture j is cooled, filtered, and the filter cake washed with'bcnzenc.'I'hefiltrate and wash liquid arecombined and distilled, I yielding 43.9gms. of yellow liquid'at; 5 4/0.6mm.68" 3= mm. product is'redistilled toyield 13.3 gms. at 15 54/ 0.95 mm.-56/1.0.mm. .The'resultant clear,yellow- 7 green liquid, 1,1,l-trichloro43-nitro 2+butene, hasthefollowing analysis:

Percent-.Cal Percent 'culated 7 Actual Constituent I I I I Part B' ,Toillustrate effectiveness as a soil fu'migant and nema- I tocide, theproduct'of' Part A is applied, to soil around I 5 squash; seeds (var.Golden Summer Crookneck) in a I I one-half gallon ceramic crock.Similartests are con i ductedu sing a soil :additivesa D'D mixture(dichloro i propane-dichloropropene' mixture) and hexachlor,ocyclo- Ipentadiene as standard materials; At, a dosage, of 0.5 I m1. nematodeinfestation: is: eflectively. controlled using .l,1,.l-trichloro 3-nitro2 butener I The, same dosage of the I 13 D mixturecontrolstheinfestationequally well. The hexachlorocyclopentadiene kills-all of the: squashseeda .adosageofllfiml. fl

I Parzgtj' Preparation of 3,3,3 trichloro-I-nitropr0pen e.This compoundis prepared according to the method described by Brower and Burkett inthe Journal of the American Chemical Society, vol. 75, No. 5, at pages1082 and 1083.

Part B To illustrate the absence of phytotoxicity,3,3,3-tricbloro-l-nitropropene at 2,000 parts per million is sprayed for40 seconds at 40 p.s.i. on 25-day old tomato plants (var. Bonny Best)and 25-day old cucumber plants. No plant injury or other phytotoxicefiects are observed in either the tomato plants or the cucumber plants.

Part C TABLE I Soil Additive Dosage, No. Gulls No. Seeds Percent M1. onPlants Emerging Control 3,3,3-Trichloro-l-Nitropropene 0, 125 17 5 96. 5D-D Mixture 0.125 17 3 96.5 I Chloropicrin 0.125 503 5 0.0 UntreatedNone 503 4 0. 0

Part D Testssimilar to those of Part C are conducted using soil infestedwith nematodes but no galls. The results, indexed comparatively, are asfollows:

The experimental results indicated in Parts C and D of Example IIclearly indicate the nematocidal efiectiveness of a compound of thepresent invention, both in comparison to an untreated infested soil andin comparison with two widely used soil fumigants.

It is to be understood that although the invention has been describedwith specific reference to certain embodiments thereof, it is not to beso limited, since changes and alterations therein may be made which arewithin the full intended scope of the invention as defined by theappended claims.

What is claimed is:

1. The method of controlling nematodes which comprises contactingnematode-infested soil 'with a nematocida1 amount of a compositionincluding as an active toxic ingredient a compound having the formulawherein n is a number from 0 to 3, inclusive, X is halogen and R isselected from the group consisting of hydrogen, lower alkyl, phenyl,.naphthyl, tolyl, xylyl, benzyl and phenethyl radicals.

2. The method of controling nematodes which comprises contactingnematode-infested soil with a nematocidal amount of a compositionincluding as an active toxic ingredient a compound having the formula 3.The method of controlling nematodes which comprises contactingnematode-infested soil with a nematocidal amount of a compositionincluding as an active toxic ingredient a compound having the formula 4.The method of controlling nematodes which comprises contactingnematode-infested soil with a nematocida1 amount of a compositionincluding as an active toxic ingredient a compound having the formula 5.The method of controlling nematodes which comprises contactingnematode-infested soil with a nematocidal amount of a compositionincluding as an active toxic ingredient a compound having the formula 6.The method of controlling nematodes which comprises contactingnematode-infested soil with a nematocidal amount of a compositionincluding as an active toxic ingredient a compound having the formulaReferences Cited in the file of this patent UNITED STATES PATENTS2,335,384 Bousquet et a1 Nov. 30, 1943 2,435,204 Davidson Feb. 3, 19482,473,341 Kooijman et a1. June 14, 1949 2,473,984 Bickerton June 21,1949 2,502,244 Carter Mar. 28, 1950 2,543,580 Kay Feb. 27, 1951 OTHERREFERENCES Frear: Chem. of the Insecticides, Fungicides and Herbicides,2nd ed., 1948, D. Van Nostrand, pp. 108-22.

Journal of the American Chemical Society, vol. 75, No. 5, pp. 1082-3(1953).

1. THE METHOD OF CONTROLLING NEMATODES WHICH COMPRISES CONTACTINGNEMATODE-INFESTED SOIL WITH A NEMATOCIDAL AMOUNT OF A COMPOSITIONINCLUDING AS AN ACTIVE TOXIC INGREDIENT A COMPOUND HAVING THE FORMULA